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arXiv:2603.11288

Quantum tomography of $H \to ZZ, WW$ beyond leading order

J. A. Aguilar-Saavedra, Pier Paolo Giardino

hep-phhep-exquant-phSubmitted Mar 11, 2026• Announced Mar 13, 2026• Revised Mar 20, 2026 (v2)
v1 · Mar 11, 2026v2 · Mar 20, 2026
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Abstract

We revisit quantum tomography of $H \to ZZ$ and $H \to WW$ in the presence of higher-order corrections. We verify that neither the use of an effective spin analysing power (only for $ZZ$) or a photon veto are sufficient to render the naively-constructed spin density operators physical. A subtraction of higher-order corrections is thus necessary to perform consistent quantum tomography. Such corrections are small when compared to expected experimental uncertainties with current data. As a by-product, we point out the striking possibility to observe parity-violating effects in $H \to WW$.

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